Suspension unit having a magneto-spring

• US 6,336,627 B1
• Filed: 02/16/2000
• Issued: 01/08/2002
• Est. Priority Date: 02/17/1999
• Status: Expired due to Fees

• Current Assignee: Delta Tooling Co., Ltd.
• Original Assignee: Delta Tooling Co., Ltd.
• Inventors: Ohshimo, Hiroki, Takata, Yasuhide, Fujita, Etsunori, Chizuka, Kazuyoshi
• Primary Examiner(s): Oberleitner, Robert J.
• Assistant Examiner(s): Pezzlo, Benjamin A.
• Application Number:
  US09/504,940
• Time in Patent Office: 692 Days
• Field of Search: 267/140.11, 267/140.4, 267/142, 267/131, 267/136, 248/562, 248/560, 248/576, 248/581, 248/589, 108/144.11, 108/145, 108/147
• US Class Current: 267/131
• CPC Class Codes: B60N 2/502 attached to the base of the seat B60N2/504 takes precedence
• CPC Class Codes: B60N 2/506 Seat guided by rods
• CPC Class Codes: B60N 2/544 Compression or tension springs B60N2/542 takes precedence
• CPC Class Codes: F16F 1/123 characterised by the ends of the spring being specially adapted, e.g. to form an eye for engagement with a radial insert F16F1/122, F16F1/125 take precedence
• CPC Class Codes: F16F 15/03 using magnetic or electromagnetic means F16F9/53, F16F15/005 take precedence
• CPC Class Codes: F16F 6/005 using permanent magnets only

Abstract

A suspension unit includes a lower frame, an upper frame vertically movably mounted on the lower frame, and two link mechanisms disposed on respective sides of the upper and lower frames for connecting them to each other. Each of the two link mechanisms includes a parallel link mechanism having two arms extending generally parallel to each other and a pantograph-shaped link mechanism having a plurality of arms. The suspension unit further includes two permanent magnets each fixedly mounted on one of the upper and lower frames with like magnetic poles opposed to each other, a metallic spring engaged with one of the pantograph-shaped link mechanisms, and a shock absorber engaged with the other of the pantograph-shaped link mechanisms that has spring properties. With such construction, vibration below a predetermined amplitude is absorbed by the spring properties of the other of the pantograph-shaped link mechanisms with the shock absorber not operated.

Claims

1. A suspension unit comprising:

a lower frame;

an upper frame vertically movably mounted on said lower frame;

two link mechanisms disposed on respective sides of said upper and lower frames for connecting said upper and lower frames to each other, each of said two link mechanisms comprising a parallel link mechanism having two arms extending generally parallel to each other and a pantograph-shaped link mechanism having first, second, third and fourth arms, said first and second arms being connected to each other at a first connecting portion, said third and fourth arms being connected to each other at a second connecting portion, said first and third arms being connected to said upper frame, and said second and fourth arms being connected to said lower frame;

two permanent magnets each fixedly mounted on one of said upper and lower frames with like magnetic poles opposed to each other;

a metallic spring engaged with one of said pantograph-shaped link mechanisms; and

a shock absorber having a first end and a second end opposite to each other, said first end being connected to said first connecting portion of one of said two link mechanisms, said second end being connected to said second connecting portion of said one of said two link mechanisms, said first and second connecting portions of said one of said two link mechanisms having respective vibration-absorbing spring properties such that vibration below a predetermined amplitude is absorbed by the spring properties of said first and second connecting portions of said one of said two link mechanisms with said shock absorber not operated.

2. The suspension unit according to claim 1, further comprising a plurality of metallic springs engaged with said upper frame and with a portion of at least one of said parallel link mechanisms for producing a lifting force of said upper frame.

3. The suspension unit according to claim 1, wherein said first and second connecting portions of said one of said two link mechanisms are arranged such that said vibration-absorbing spring properties thereof act in a direction axially of said shock absorber.

4. The suspension unit according to claim 3, wherein said first and second connecting portions of said one of said two link mechanisms are arranged such that said vibration-absorbing spring properties thereof act in a direction in which each of said first and second ends of said shock absorber slides.

5. The suspension unit according to claim 1, wherein said one of said pantograph-shaped link mechanisms with which said metallic spring is engaged is part of the other of said two link mechanisms.

6. The suspension unit according to claim 5, wherein said metallic spring comprises first and second ends opposite to each other, and said first and second ends of said metallic spring are respectively connected to said first and second connecting portions of said other of said two link mechanisms.

7. The suspension unit according to claim 1, wherein said metallic spring comprises first and second ends opposite to each other, and said first and second ends of said metallic spring are respectively connected to said first and second connecting portions of the other of said two link mechanisms.